Bug 157347 – Media elements should not be paused right away when removed from the document

• Component: Media
• Status: RESOLVED FIXED

[Chris Dumez]

Media elements should not be paused right away when removed from the document. Instead we should allow the task that removed the media element from the document to finish because considering pausing.
This avoid inadvertently pausing media elements when the JS merely moves them on the page (e.g. using Node.replaceChild()).

Text from the HTML specification:
"""
When a media element is removed from a Document, the user agent must run the following steps:
1.  Await a stable state, allowing the task that removed the media element from the Document to continue. The synchronous section consists of all the remaining steps of this algorithm. (Steps in the synchronous section are marked with ⌛.)
2. ⌛ If the media element is in a Document, abort these steps.
3. ⌛ Run the internal pause steps for the media element.

"""

c.f. https://html.spec.whatwg.org/multipage/embedded-content.html#htmlmediaelement

[Chris Dumez]

<rdar://problem/25888758>

[Chris Dumez]

Created attachment 278122 [details]
Patch

[Chris Dumez]

Comment on attachment 278122 [details]
Patch

Clearing flags on attachment: 278122

Committed r200431: <http://trac.webkit.org/changeset/200431>

[Chris Dumez]

All reviewed patches have been landed.  Closing bug.

[Darin Adler]

Comment on attachment 278122 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=278122&action=review

> Source/WebCore/dom/GenericEventQueue.cpp:81
> +    Deque<WeakPtr<GenericEventQueue>> queuedEvents;
> +    std::swap(queuedEvents, pendingQueues());

Why swap instead of move here?